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Rosa-Caldwell ME, Brown JL, Lee DE, Wiggs MP, Perry RA, Haynie WS, Caldwell AR, Washington TA, Lo WJ, Greene NP. Hepatic alterations during the development and progression of cancer cachexia. Appl Physiol Nutr Metab 2019; 45:500-512. [PMID: 31618604 DOI: 10.1139/apnm-2019-0407] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Cancer-associated bodyweight loss (cachexia) is a hallmark of many cancers and is associated with decreased quality of life and increased mortality. Hepatic function can dramatically influence whole-body energy expenditure and may therefore significantly influence whole-body health during cancer progression. The purpose of this study was to examine alterations in markers of hepatic metabolism and physiology during cachexia progression. Male C57BL/6J mice were injected with 1 × 106 Lewis Lung Carcinoma cells dissolved in 100 μL PBS and cancer was allowed to develop for 1, 2, 3, or 4 weeks. Control animals were injected with an equal volume of phosphate-buffered saline. Livers were analyzed for measures of metabolism, collagen deposition, protein turnover, and mitochondrial quality. Animals at 4 weeks had ∼30% larger livers compared with all other groups. Cancer progression was associated with altered regulators of fat metabolism. Additionally, longer duration of cancer development was associated with ∼3-fold increased regulators of collagen deposition as well as phenotypic collagen content, suggesting increased liver fibrosis. Mitochondrial quality control regulators appeared to be altered before any phenotypic alterations to collagen deposition. While induction of Akt was noted, downstream markers of protein synthesis were not altered. In conclusions, cancer cachexia progression is associated with hepatic pathologies, specifically liver fibrosis. Alterations to mitochondrial quality control mechanisms appear to precede this fibrotic phenotype, potentially suggesting mitochondrial mechanisms for the development of hepatic pathologies during the development and progression of cancer cachexia. Novelty Cachexia progression results in liver collagen deposition and fibrosis. Alterations in mitochondrial quality control may precede liver pathologies during cachexia.
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Affiliation(s)
- Megan E Rosa-Caldwell
- Integrative Muscle Metabolism Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Jacob L Brown
- Integrative Muscle Metabolism Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - David E Lee
- Integrative Muscle Metabolism Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Michael P Wiggs
- Department of Health and Kinesiology, University of Texas at Tyler, Tyler, TX 75799, USA
| | - Richard A Perry
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, USA
| | - Wesley S Haynie
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, USA
| | - Aaron R Caldwell
- Exercise Science Research Center, Department of Health, Human Performance, and Recreation, University of Arkansas, Fayetteville, Arkansas, USA
| | - Tyrone A Washington
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas, USA
| | - Wen-Juo Lo
- Department of Rehabilitation, Human Resources, and Communication Disorders, University of Arkansas, Fayetteville, Arkansas, USA
| | - Nicholas P Greene
- Integrative Muscle Metabolism Laboratory, Exercise Science Research Center, University of Arkansas, Fayetteville, Arkansas 72701, USA
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52
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Lajtai K, Nagy CT, Tarszabó R, Benkő R, Hadjadj L, Sziva RE, Gerszi D, Bányai B, Ferdinandy P, Nádasy GL, Giricz Z, Horváth EM, Várbíró S. Effects of Vitamin D Deficiency on Proliferation and Autophagy of Ovarian and Liver Tissues in a Rat Model of Polycystic Ovary Syndrome. Biomolecules 2019; 9:biom9090471. [PMID: 31509973 PMCID: PMC6770417 DOI: 10.3390/biom9090471] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/28/2019] [Accepted: 09/06/2019] [Indexed: 12/26/2022] Open
Abstract
Aim: We aimed to examine the alterations of the insulin signaling pathway, autophagy, nitrative stress and the effect of vitamin D supplementation in the liver and ovaries of vitamin D deficient hyperandrogenic rats. Methods: Female Wistar rats received eight weeks of transdermal testosterone treatment and lived on a low vitamin D diet (D–T+). Vitamin D supplementation was achieved by oral administration of vitamin D3 (D+T+). Sham-treated (D+T–) and vitamin D deficient animals (D–T–) served as controls. (N = 10–12 per group). Results: D–T+ animals showed decreased LC3 II levels in the liver and increased p-Akt/Akt and p-eNOS/eNOS ratios with decreased insulin receptor staining in the ovaries. Vitamin D supplementation prevented the increase of Akt phosphorylation in the ovaries. Vitamin D deficiency itself also led to decreased LC3 II levels in the liver and decreased insulin receptor staining in the ovaries. D–T+ group showed no increase in nitrotyrosine staining; however, the ovaries of D–T– rats and the liver of D+T+ animals showed increased staining intensity. Conclusion: Vitamin D deficiency itself might lead to disrupted ovarian maturation and autophagy malfunction in the liver. Preventing Akt phosphorylation may contribute to the beneficial effect of vitamin D treatment on ovarian function in hyperandrogenism.
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Affiliation(s)
- Krisztina Lajtai
- Department of Obstetrics and Gynecology, Semmelweis University, Üllői út 78/a, 1082 Budapest, Hungary.
| | - Csilla Terézia Nagy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Nagyvárad tér 4, 1089 Budapest, Hungary.
| | - Róbert Tarszabó
- Department of Physiology, Semmelweis University, Tűzoltó utca 37-47, 1094 Budapest, Hungary.
| | - Rita Benkő
- Department of Physiology, Semmelweis University, Tűzoltó utca 37-47, 1094 Budapest, Hungary.
| | - Leila Hadjadj
- Institute of Clinical Experimental Research, Semmelweis University, Tűzoltó utca 37-47, 1094 Budapest, Hungary.
| | - Réka Eszter Sziva
- Department of Obstetrics and Gynecology, Semmelweis University, Üllői út 78/a, 1082 Budapest, Hungary.
| | - Dóra Gerszi
- Department of Obstetrics and Gynecology, Semmelweis University, Üllői út 78/a, 1082 Budapest, Hungary.
- Department of Physiology, Semmelweis University, Tűzoltó utca 37-47, 1094 Budapest, Hungary.
| | - Bálint Bányai
- Department of Physiology, Semmelweis University, Tűzoltó utca 37-47, 1094 Budapest, Hungary.
| | - Péter Ferdinandy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Nagyvárad tér 4, 1089 Budapest, Hungary.
| | - György László Nádasy
- Department of Physiology, Semmelweis University, Tűzoltó utca 37-47, 1094 Budapest, Hungary.
| | - Zoltán Giricz
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, Nagyvárad tér 4, 1089 Budapest, Hungary.
| | - Eszter Mária Horváth
- Department of Physiology, Semmelweis University, Tűzoltó utca 37-47, 1094 Budapest, Hungary.
| | - Szabolcs Várbíró
- Department of Obstetrics and Gynecology, Semmelweis University, Üllői út 78/a, 1082 Budapest, Hungary.
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53
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He J, Ding J, Lai Q, Wang X, Li A, Liu S. Irbesartan Ameliorates Lipid Deposition by Enhancing Autophagy via PKC/AMPK/ULK1 Axis in Free Fatty Acid Induced Hepatocytes. Front Physiol 2019; 10:681. [PMID: 31191364 PMCID: PMC6548903 DOI: 10.3389/fphys.2019.00681] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 05/13/2019] [Indexed: 01/17/2023] Open
Abstract
Irbesartan has shown significant therapeutic effects in hypertensive patients with non-alcoholic fatty liver disease (NAFLD). To determine the underlying mechanisms of its action, we established an in vitro model of NAFLD by treating human and mouse hepatocytes with free fatty acids (FFAs) and angiotensin (Ang) II. Irbesartan significantly reversed AngII/FFA-induced lipid deposition and mitochondrial dysfunction by restoring ATP production and the mitochondrial membrane potential (MMP), and decreasing the levels of reactive oxygen species (ROS) and inflammatory markers. In addition, irbesartan also increased the autophagy flux, in terms of increased numbers of autolysosomes and autophagosomes, and the upregulation and mitochondrial localization of the autophagic proteins Atg5 and LC3BII/I. Activation of protein kinase C (PKC) and inhibition of the autophagic flux exacerbated mitochondrial dysfunction in the steatotic hepatocytes. Furthermore, AngII upregulated PKC which inhibited AMPK phosphorylation via direct interaction with the AngII receptor AT1-R. Irbesartan inhibited PKC and activated AMPK and its downstream effector ULK1, thereby inducing autophagy, decreasing lipid deposition, and restoring mitochondrial function. Taken together, irbesartan triggers autophagy via the PKC/AMPK/ULK1 axis to ameliorate the pathological changes in the steatotic hepatocytes.
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Affiliation(s)
- Juan He
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jian Ding
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qiuhua Lai
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xinke Wang
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Aimin Li
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Side Liu
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
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Li YL, Li XQ, Wang YD, Shen C, Zhao CY. Metformin alleviates inflammatory response in non-alcoholic steatohepatitis by restraining signal transducer and activator of transcription 3-mediated autophagy inhibition in vitro and in vivo. Biochem Biophys Res Commun 2019; 513:64-72. [DOI: 10.1016/j.bbrc.2019.03.077] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 03/14/2019] [Indexed: 02/06/2023]
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55
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Oleate inhibits hepatic autophagy through p38 mitogen-activated protein kinase (MAPK). Biochem Biophys Res Commun 2019; 514:92-97. [PMID: 31023527 DOI: 10.1016/j.bbrc.2019.04.073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 04/10/2019] [Indexed: 12/19/2022]
Abstract
Hepatic autophagy plays an important role in lipid metabolism, especially in nonalcoholic fatty liver disease. The relationship between Oleate acid and autophagy is not yet clear. In this work, using mouse epithelial cell hepa1c1c7, we investigated the role of Oleate acid on autophagy and explored its potential mechanisms. The exposure of hepatic cells to Oleate acid resulted in a significant reduction of LC3 accumulation together with enhancement of p62 protein expression and the mRNA levels of ATG7 and BECN1 were reduced as well. Mechanistically, the inhibitory effects of Oleate acid on rapamycin-induced autophagy were completely blocked by treatment with dominant negative p38α and p38 inhibitor SB203580. Furthermore, ATF-2, downstream of p38, was activated by Oleate treatment. Oleate treatment also inhibited the ULK1 promoter and decreased the ULK1 mRNA level. Our data therefore suggest that Oleate activated the ATF-2 via p38 kinase which inhibited the ULK1 via binding to ULK1 promoter, and eventually the rapamycin-induced autophagy was suppressed.
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56
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Chi HC, Tsai CY, Tsai MM, Yeh CT, Lin KH. Molecular functions and clinical impact of thyroid hormone-triggered autophagy in liver-related diseases. J Biomed Sci 2019; 26:24. [PMID: 30849993 PMCID: PMC6407245 DOI: 10.1186/s12929-019-0517-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 02/26/2019] [Indexed: 02/07/2023] Open
Abstract
The liver is controlled by several metabolic hormones, including thyroid hormone, and characteristically displays high lysosomal activity as well as metabolic stress-triggered autophagy, which is stringently regulated by the levels of hormones and metabolites. Hepatic autophagy provides energy through catabolism of glucose, amino acids and free fatty acids for starved cells, facilitating the generation of new macromolecules and maintenance of the quantity and quality of cellular organelles, such as mitochondria. Dysregulation of autophagy and defective mitochondrial homeostasis contribute to hepatocyte injury and liver-related diseases, such as non-alcoholic fatty liver disease (NAFLD) and liver cancer. Thyroid hormones (TH) mediate several critical physiological processes including organ development, cell differentiation, metabolism and cell growth and maintenance. Accumulating evidence has revealed dysregulation of cellular TH activity as the underlying cause of several liver-related diseases, including alcoholic or non-alcoholic fatty liver disease and liver cancer. Data from epidemiologic, animal and clinical studies collectively support preventive functions of THs in liver-related diseases, highlighting the therapeutic potential of TH analogs. Elucidation of the molecular mechanisms and downstream targets of TH should thus facilitate the development of therapeutic strategies for a number of major public health issues. Here, we have reviewed recent studies focusing on the involvement of THs in hepatic homeostasis through induction of autophagy and their implications in liver-related diseases. Additionally, the potential underlying molecular pathways and therapeutic applications of THs in NAFLD and HCC are discussed.
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Affiliation(s)
- Hsiang-Cheng Chi
- Radiation Biology Research Center, Institute for Radiological Research, Chang Gung University/Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan
| | - Chung-Ying Tsai
- Kidney Research Center and Department of Nephrology, Chang Gung Immunology Consortium, Chang Gung Memorial Hospital, Taoyuan, 333, Taiwan
| | - Ming-Ming Tsai
- Department of Nursing, Chang-Gung University of Science and Technology, Taoyuan, Taiwan, 333.,Department of General Surgery, Chang Gung Memorial Hospital, Chiayi, Taiwan, 613.,Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology , Taoyuan, Taiwan
| | - Chau-Ting Yeh
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan, 333
| | - Kwang-Huei Lin
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan, 333. .,Department of Biochemistry, College of Medicine, Chang-Gung University, 259 Wen-Hwa 1 Road, Taoyuan, 333, Taiwan, Republic of China. .,Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology , Taoyuan, Taiwan.
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57
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Xu S, Sui S, Zhang X, Pang B, Wan L, Pang D. Modulation of autophagy in human diseases strategies to foster strengths and circumvent weaknesses. Med Res Rev 2019; 39:1953-1999. [PMID: 30820989 DOI: 10.1002/med.21571] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 01/20/2019] [Accepted: 02/05/2019] [Indexed: 12/19/2022]
Abstract
Autophagy is central to the maintenance of intracellular homeostasis across species. Accordingly, autophagy disorders are linked to a variety of diseases from the embryonic stage until death, and the role of autophagy as a therapeutic target has been widely recognized. However, autophagy-associated therapy for human diseases is still in its infancy and is supported by limited evidence. In this review, we summarize the landscape of autophagy-associated diseases and current autophagy modulators. Furthermore, we investigate the existing autophagy-associated clinical trials, analyze the obstacles that limit their progress, offer tactics that may allow barriers to be overcome along the way and then discuss the therapeutic potential of autophagy modulators in clinical applications.
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Affiliation(s)
- Shouping Xu
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Shiyao Sui
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Xianyu Zhang
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Boran Pang
- Department of Surgery, Rui Jin Hospital, Shanghai Key Laboratory of Gastric Neoplasm, Shanghai Institute of Digestive Surgery, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lin Wan
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Da Pang
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
- Heilongjiang Academy of Medical Sciences, Harbin, Heilongjcontrary, induction of autophagy elongiang, China
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58
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Chu Q, Zhang S, Chen M, Han W, Jia R, Chen W, Zheng X. Cherry Anthocyanins Regulate NAFLD by Promoting Autophagy Pathway. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:4825949. [PMID: 30931080 PMCID: PMC6410467 DOI: 10.1155/2019/4825949] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 12/28/2018] [Accepted: 01/15/2019] [Indexed: 01/09/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a common chronic disease that threatens human health, and present therapies remain limited due to the lack of effective drugs. Lipid metabolic disturbance and oxidative stress have strong links to the development of NAFLD, while autophagy was generally accepted as a key regulatory mechanism on these steps. Our previous studies indicated that cherry anthocyanins (CACN) protected against high fat diet-induced obesity and NALFD in C57BL/6 mice, while the underlying molecule mechanism is still unclear. Thus, in this study, we show that CACN protect against oleic acid- (OA-) induced oxidative stress and attenuate lipid droplet accumulation in NAFLD cell models. According to the results of a transmission electron microscope (TEM), western blot, immunofluorescence (IF), and adenovirus transfection (Ad-mCherry-GFP-LC3B), autophagy is in accordance with the lipid-lowering effect induced by CACN. Further studies illustrate that CACN may activate autophagy via mTOR pathways. In addition, an autophagy inhibitor, 3-methyladenine (3-MA), was applied and the result suggested that autophagy indeed participates in the lipid clearance process in OA-induced lipid accumulation. All these results indicate that the positive effects of CACN on OA-induced hepatic lipid accumulation are mediated via activating autophagy, showing a potential target for the therapeutic strategy of NAFLD.
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Affiliation(s)
- Qiang Chu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China
- Zhejiang Key Laboratory for Agro-food Processing, Zhejiang University, Hangzhou 310058, China
- Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Shuang Zhang
- College of Environmental and Resource Science, Zhejiang University, Hangzhou 310058, China
| | - Meng Chen
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China
- Zhejiang Key Laboratory for Agro-food Processing, Zhejiang University, Hangzhou 310058, China
- Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Wen Han
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China
- Zhejiang Key Laboratory for Agro-food Processing, Zhejiang University, Hangzhou 310058, China
- Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Ruoyi Jia
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China
- Zhejiang Key Laboratory for Agro-food Processing, Zhejiang University, Hangzhou 310058, China
- Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Wen Chen
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China
- Zhejiang Key Laboratory for Agro-food Processing, Zhejiang University, Hangzhou 310058, China
- Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
| | - Xiaodong Zheng
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China
- Zhejiang Key Laboratory for Agro-food Processing, Zhejiang University, Hangzhou 310058, China
- Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China
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59
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Gjorgjieva M, Mithieux G, Rajas F. Hepatic stress associated with pathologies characterized by disturbed glucose production. Cell Stress 2019; 3:86-99. [PMID: 31225503 PMCID: PMC6551742 DOI: 10.15698/cst2019.03.179] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The liver is an organ with many facets, including a role in energy production and metabolic balance, detoxification and extraordinary capacity of regeneration. Hepatic glucose production plays a crucial role in the maintenance of normal glucose levels in the organism i.e. between 0.7 to 1.1 g/l. The loss of this function leads to a rare genetic metabolic disease named glycogen storage disease type I (GSDI), characterized by severe hypoglycemia during short fasts. On the contrary, type 2 diabetes is characterized by chronic hyperglycemia, partly due to an overproduction of glucose by the liver. Indeed, diabetes is characterized by increased uptake/production of glucose by hepatocytes, leading to the activation of de novo lipogenesis and the development of a non-alcoholic fatty liver disease. In GSDI, the accumulation of glucose-6 phosphate, which cannot be hydrolyzed into glucose, leads to an increase of glycogen stores and the development of hepatic steatosis. Thus, in these pathologies, hepatocytes are subjected to cellular stress mainly induced by glucotoxicity and lipotoxicity. In this review, we have compared hepatic cellular stress induced in type 2 diabetes and GSDI, especially oxidative stress, autophagy deregulation, and ER-stress. In addition, both GSDI and diabetic patients are prone to the development of hepatocellular adenomas (HCA) that occur on a fatty liver in the absence of cirrhosis. These HCA can further acquire malignant traits and transform into hepatocellular carcinoma. This process of tumorigenesis highlights the importance of an optimal metabolic control in both GSDI and diabetic patients in order to prevent, or at least to restrain, tumorigenic activity during disturbed glucose metabolism pathologies.
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Affiliation(s)
- Monika Gjorgjieva
- Institut National de la Santé et de la Recherche Médicale, U1213, Lyon, F-69008, France.,Université de Lyon, Lyon, F-69008 France.,Université Lyon I, Villeurbanne, F-69622 France
| | - Gilles Mithieux
- Institut National de la Santé et de la Recherche Médicale, U1213, Lyon, F-69008, France.,Université de Lyon, Lyon, F-69008 France.,Université Lyon I, Villeurbanne, F-69622 France
| | - Fabienne Rajas
- Institut National de la Santé et de la Recherche Médicale, U1213, Lyon, F-69008, France.,Université de Lyon, Lyon, F-69008 France.,Université Lyon I, Villeurbanne, F-69622 France
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60
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Yu HH, Hsieh MC, Wu SY, Sy ED, Shan YS. Effects of duodenal-jejunal bypass surgery in ameliorating nonalcoholic steatohepatitis in diet-induced obese rats. Diabetes Metab Syndr Obes 2019; 12:149-159. [PMID: 30705600 PMCID: PMC6342211 DOI: 10.2147/dmso.s190631] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Duodenal-jejunal bypass (DJB) is an important component of many types of current bariatric surgery including Roux-en-Y gastric bypass, mini-gastric bypass, biliopancreatic diversion, duodenal switch, and DJB plus sleeve gastrectomy. Surgery is often observed to ameliorate nonalcoholic steatohepatitis (NASH), but without a clearly delineated mechanism. In this study, we investigated the effects of DJB in diet-induced obese rats with NASH. MATERIALS AND METHODS Male Wistar rats were divided into four groups and fed the following diets over 6 months: A) normal chow (NC group, n=6); B) methionine-choline-deficient (MCD)-high-fat (HF) diet (HF group, n=6); C) MCD-HF diet for 3 months followed by DJB and MCD-HF diet for subsequent 3 months (DJB group, n=6); and D) MCD-HF diet for 3 months followed by treatment with pioglitazone (PGZ) with MCD-HF diet for subsequent 3 months (PGZ group, n=6). Body weight, glucose tolerance, the homeostatic model assessment-insulin resistance index, and lipid profiles were compared. Liver and visceral adipose tissue histology, inflammatory marker and hepatic stellate cell (HSC) activity, and hepatocyte autophagy were assessed. RESULTS Compared with the HF group, the DJB group showed improved body weight, insulin sensitivity, lipid metabolism, and steatosis severity. The DJB group exhibited a significantly lower nonalcoholic fatty liver disease activity score than the HF and PGZ group (P<0.001 and P=0.003, respectively). Furthermore, DJB significantly reduced fat mass and adipocyte size. These effects were also observed in the PGZ group. Therefore, we speculated that the improvements induced by DJB are closely related to an alteration in insulin sensitivity. Moreover, DJB reduced HSC activity and TNF-α expression and enhanced hepatocyte autophagy. CONCLUSION DJB improves NASH through several mechanisms, particularly by altering insulin sensitivity, inflammatory responses, HSC activity, and hepatocyte autophagy.
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Affiliation(s)
- Hsin-Hsien Yu
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan,
- Division of General Surgery, Department of Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
- Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Mao-Chih Hsieh
- Division of General Surgery, Department of Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
- Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Szu-Yuan Wu
- Department of Radiation Oncology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Edgar D Sy
- Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan,
| | - Yan-Shen Shan
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan,
- Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan,
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61
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Oleuropein Induces AMPK-Dependent Autophagy in NAFLD Mice, Regardless of the Gender. Int J Mol Sci 2018; 19:ijms19123948. [PMID: 30544824 PMCID: PMC6321282 DOI: 10.3390/ijms19123948] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/30/2018] [Accepted: 12/07/2018] [Indexed: 12/12/2022] Open
Abstract
Oleuropein (Ole) is one of the most plentiful phenolic compounds with antioxidant, anti-inflammatory, anti-atherogenic, hypoglycemic and hypolipidemic effects. The aim of our study was to establish whether the positive Ole-related effects on liver steatosis could be associated with autophagy. Female and male C57BL/6J mice were fed normal diet (ND) or high-fat diet (HFD) for eight weeks, and Ole was added or not for the following eight weeks. The autophagy-related proteins Akt, mTOR, AMPK, ULK1, Beclin-1, LC3B and p62/Sqstm1 were analyzed. Interestingly, Ole induced a different regulation of the Akt/mTOR pathway in female compared to male mice, but was able to activate the autophagic process in ND and HFD mice through AMPK-dependent phosphorylation of ULK1 at Ser555, regardless of the gender. Our work reveals the ability of Ole to induce, in liver of ND and HFD mice, autophagy independently by gender-specific mTOR activation. We highlight Ole as a novel therapeutic approach to counteract unhealthy diet-related liver steatosis by targeting autophagy.
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62
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Finck BN. Targeting Metabolism, Insulin Resistance, and Diabetes to Treat Nonalcoholic Steatohepatitis. Diabetes 2018; 67:2485-2493. [PMID: 30459251 PMCID: PMC6245219 DOI: 10.2337/dbi18-0024] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 09/20/2018] [Indexed: 12/25/2022]
Abstract
Obesity, insulin resistance, and diabetes are strongly linked to the accumulation of excessive lipids in the liver parenchyma, a condition known as nonalcoholic fatty liver disease (NAFLD). Given its association with obesity and related metabolic diseases, it is not surprising that the prevalence of NAFLD has dramatically increased in the past few decades. NAFLD has become the most common liver disease in many areas of the world. The term, NAFLD, encompasses a spectrum of disorders that ranges from simple steatosis to steatosis with inflammatory lesions (nonalcoholic steatohepatitis [NASH]). Although simple steatosis might be relatively benign, epidemiologic studies have linked NASH to greatly increased risk of developing cirrhosis and hepatocellular carcinoma. Yet despite this, there are no approved treatments for the disease, and it remains a significant unmet medical need. This Perspective will review some of the relevant literature on the topic and examine approved and experimental NASH therapeutic concepts that target intermediary metabolism, insulin resistance, and diabetes to treat this emerging public health problem.
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Affiliation(s)
- Brian N Finck
- Center for Human Nutrition, Division of Geriatrics and Nutritional Sciences, John T. Milliken Department of Medicine, Washington University School of Medicine in St. Louis, St. Louis, MO
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63
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Bessone F, Dirchwolf M, Rodil MA, Razori MV, Roma MG. Review article: drug-induced liver injury in the context of nonalcoholic fatty liver disease - a physiopathological and clinical integrated view. Aliment Pharmacol Ther 2018; 48:892-913. [PMID: 30194708 DOI: 10.1111/apt.14952] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 03/25/2018] [Accepted: 07/30/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND Nonalcoholic fatty disease (NAFLD) is the most common liver disease, since it is strongly associated with obesity and metabolic syndrome pandemics. NAFLD may affect drug disposal and has common pathophysiological mechanisms with drug-induced liver injury (DILI); this may predispose to hepatoxicity induced by certain drugs that share these pathophysiological mechanisms. In addition, drugs may trigger fatty liver and inflammation per se by mimicking NAFLD pathophysiological mechanisms. AIMS To provide a comprehensive update on (a) potential mechanisms whereby certain drugs can be more hepatotoxic in NAFLD patients, (b) the steatogenic effects of drugs, and (c) the mechanism involved in drug-induced steatohepatitis (DISH). METHODS A language- and date-unrestricted Medline literature search was conducted to identify pertinent basic and clinical studies on the topic. RESULTS Drugs can induce macrovesicular steatosis by mimicking NAFLD pathogenic factors, including insulin resistance and imbalance between fat gain and loss. Other forms of hepatic fat accumulation exist, such as microvesicular steatosis and phospholipidosis, and are mostly associated with acute mitochondrial dysfunction and defective lipophagy, respectively. Drug-induced mitochondrial dysfunction is also commonly involved in DISH. Patients with pre-existing NAFLD may be at higher risk of DILI induced by certain drugs, and polypharmacy in obese individuals to treat their comorbidities may be a contributing factor. CONCLUSIONS The relationship between DILI and NAFLD may be reciprocal: drugs can cause NAFLD by acting as steatogenic factors, and pre-existing NAFLD could be a predisposing condition for certain drugs to cause DILI. Polypharmacy associated with obesity might potentiate the association between this condition and DILI.
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Affiliation(s)
- Fernando Bessone
- Hospital Provincial del Centenario, Facultad de Ciencias Médicas, Servicio de Gastroenterología y Hepatología, Universidad Nacional de Rosario, Rosario, Argentina
| | - Melisa Dirchwolf
- Unidad de Transplante Hepático, Servicio de Hepatología, Hospital Privado de Rosario, Rosario, Argentina
| | - María Agustina Rodil
- Hospital Provincial del Centenario, Facultad de Ciencias Médicas, Servicio de Gastroenterología y Hepatología, Universidad Nacional de Rosario, Rosario, Argentina
| | - María Valeria Razori
- Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Marcelo G Roma
- Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
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64
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Dethlefsen MM, Kristensen CM, Tøndering AS, Lassen SB, Ringholm S, Pilegaard H. Impact of liver PGC-1α on exercise and exercise training-induced regulation of hepatic autophagy and mitophagy in mice on HFF. Physiol Rep 2018; 6:e13731. [PMID: 29962089 PMCID: PMC6026591 DOI: 10.14814/phy2.13731] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 01/01/2023] Open
Abstract
Hepatic autophagy has been shown to be regulated by acute exercise and exercise training. Moreover, high-fat diet-induced steatosis has been reported to be associated with impaired hepatic autophagy. In addition, autophagy has been shown to be regulated by acute exercise and exercise training in a PGC-1α dependent manner in skeletal muscle. The aim of this study was to test the hypotheses that high-fat high-fructose (HFF) diet changes hepatic autophagy and mitophagy, that exercise training can restore this through a PGC-1α-mediated mechanism, and that acute exercise regulates autophagy and mitophagy in the liver. Liver samples were obtained from liver-specific PGC-1α KO mice and their littermate Lox/Lox mice fed a HFF diet or a control diet for 13 weeks. The HFF mice were either exercise trained (ExT) on a treadmill the final 5 weeks or remained sedentary (UT). In addition, half of each group performed at the end of the intervention an acute 1 h exercise bout. HFF resulted in increased hepatic BNIP3 dimer and Parkin protein, while exercise training increased BNIP3 total protein without affecting the elevated BNIP3 dimer protein. In addition, exercise training reversed a HFF-induced increase in hepatic LC3II/LC3I protein ratio, as well as a decreased PGC-1α mRNA level. Acute exercise increased hepatic PGC-1α mRNA in HFF UT mice only. In conclusion, this indicates that exercise training in part reverses a HFF-induced increase in hepatic autophagy and capacity for mitophagy in a PGC-1α-independent manner. Moreover, HFF may blunt acute exercise-induced regulation of hepatic autophagy.
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Affiliation(s)
- Maja M. Dethlefsen
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Caroline M. Kristensen
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Anna S. Tøndering
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Signe B. Lassen
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Stine Ringholm
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Henriette Pilegaard
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
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65
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Abstract
Nonalcoholic fatty liver disease (NAFLD) is a kind of liver lipid synthesis and degradation imbalance related with metabolic syndrome. Celecoxib shows the function of ameliorating NAFLD, but the underlying mechanisms remain unknown. Here, we discuss the possible mechanisms of celecoxib alleviating NAFLD by restoring autophagic flux. Lipids were accumulated in L02 cells treated with palmitate as well as SD rats fed with high-fat diet. Western blot showed that LC3 II/I was higher and p62 was lower on the early stage of steatosis while on the late stage both of them were higher, indicating that autophagic flux was activated on the early stage of steatosis, but blocked on the late stage. Rapamycin alleviated steatosis with activating autophagic flux while chloroquine aggravated steatosis with inhibiting autophagic flux. COX-2 siRNA and celecoxib were used to inhibit COX-2. Western blot and RFP-GFP-LC3 double fluorescence system indicated that celecoxib could ameliorate steatosis and restore autophagic flux in L02 cells treated with palmitate as well as SD rats fed with high-fat diet. In conclusion, celecoxib partially restores autophagic flux via downregulation of COX-2 and alleviates steatosis in vitro and in vivo.
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66
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Ischemic preconditioning attenuates ischemia/reperfusion injury in rat steatotic liver: role of heme oxygenase-1-mediated autophagy. Oncotarget 2018; 7:78372-78386. [PMID: 27852058 PMCID: PMC5346646 DOI: 10.18632/oncotarget.13281] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 11/02/2016] [Indexed: 01/22/2023] Open
Abstract
Steatotic livers are more susceptible to ischemia/reperfusion (I/R) injury, which is ameliorated by ischemic preconditioning (IPC). Autophagy possesses protective action on liver I/R injury and declines in steatotic livers. The aim of this study was to test the hypothesis that the increased susceptibility of steatotic livers to I/R injury was associated with defective hepatic autophagy, which could be restored by IPC via heme oxygenase-1 (HO-1) signaling. Obesity and hepatic steatosis was induced using a high fat diet. Obesity impaired hepatic autophagy activity and decreased hepatic HO-1 expression. Induction of HO-1 restored autophagy activity and inhibited calpain 2 activity. Additionally, suppression of calpain 2 activity also restored autophagy activity. Mitochondrial dysfunction and hepatocellular injury were significantly increased in steatotic livers compared to lean livers in response to I/R injury. This increase in sensitivity to I/R injury was associated with defective hepatic autophagy activity in steatotic livers. IPC increased autophagy and reduced mitochondrial dysfunction and hepatocellular damage in steatotic livers following I/R injury. Furthermore, IPC increased HO-1 expression. Inhibition of HO-1 decreased the IPC-induced autophagy, increased calpain 2 activity and diminished the protective effect of IPC against I/R injury. Inhibition of calpain 2 restored autophagic defect and attenuated mitochondrial dysfunction in steatotic livers after I/R. Collectively, IPC might ameliorate steatotic liver damage and restore mitochondrial function via HO-1-mediated autophagy.
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67
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Li S, Tan HY, Wang N, Cheung F, Hong M, Feng Y. The Potential and Action Mechanism of Polyphenols in the Treatment of Liver Diseases. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:8394818. [PMID: 29507653 PMCID: PMC5817364 DOI: 10.1155/2018/8394818] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 01/09/2018] [Indexed: 12/16/2022]
Abstract
Liver disease, involving a wide range of liver pathologies from fatty liver, hepatitis, and fibrosis to cirrhosis and hepatocellular carcinoma, is a serious health problem worldwide. In recent years, many natural foods and herbs with abundant phytochemicals have been proposed as health supplementation for patients with hepatic disorders. As an important category of phytochemicals, natural polyphenols have attracted increasing attention as potential agents for the prevention and treatment of liver diseases. The striking capacities in remitting oxidative stress, lipid metabolism, insulin resistance, and inflammation put polyphenols in the spotlight for the therapies of liver diseases. It has been reported that many polyphenols from a wide range of foods and herbs exert therapeutic effects on liver injuries via complicated mechanisms. Therefore, it is necessary to have a systematical review to sort out current researches to help better understand the potentials of polyphenols in liver diseases. In this review, we aim to summarize and update the existing evidence of natural polyphenols in the treatment of various liver diseases by in vitro, in vivo, and clinical studies, while special attention is paid to the action mechanisms.
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Affiliation(s)
- Sha Li
- School of Chinese Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Hor Yue Tan
- School of Chinese Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Ning Wang
- School of Chinese Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
- Shenzhen Institute of Research and Innovation, Pok Fu Lam, The University of Hong Kong, Hong Kong
| | - Fan Cheung
- School of Chinese Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Ming Hong
- School of Chinese Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yibin Feng
- School of Chinese Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong
- Shenzhen Institute of Research and Innovation, Pok Fu Lam, The University of Hong Kong, Hong Kong
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68
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Cheng C, Deng X, Xu K. Increased expression of sterol regulatory element binding protein‑2 alleviates autophagic dysfunction in NAFLD. Int J Mol Med 2018; 41:1877-1886. [PMID: 29336468 PMCID: PMC5810215 DOI: 10.3892/ijmm.2018.3389] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 01/10/2018] [Indexed: 12/25/2022] Open
Abstract
Sterol regulatory element binding protein-2 (SREBP-2) is an important transcription factor in lipid homeostasis. A previous study showed that SREBP-2 also activated autophagic genes during cell-sterol depletion. Alterations in autophagy are reported to be involved in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). However, whether the regulation of SREBP-2 restores dysfunctional autophagy in hepatocytes during NAFLD remains to be elucidated. In the present study, a steatosis model was established with palmitic acid (PA) treatment at the indicated times and concentrations. Autophagosomes in hepatocytes were visualized by confocal microscopy after transfection with a tandem GFP-mCherry-LC3 construct. Autophagy-associated protein levels were analyzed by western blot analysis. Loss- and gain-of-function studies were performed to examine the role of SREBP-2 in the regulation of hepatocyte autophagy. It was demonstrated that PA induced autophagy and enhanced autophagic flux at the early stage, whereas prolonged treatment with PA resulted in dysfunction of autophagy in the PA-induced steatotic hepatocytes. In addition, different cellular models presented with differing dysfunctional autophagy in response to fatty acid overload. It was also confirmed that SREBP-2 regulated autophagy-related gene expression in hepatocytes, and it was shown that the overexpression of SREBP-2 increased the expression of autophagy-related genes, but did not affect the inhibition of the autophagic flux in lipid-overloaded HL-7702 cells. By contrast, increased SREBP-2 partly restored the inhibited autophagic activity in lipid-overloaded hepatoma HepG2 cells. Taken together, the present study demonstrated that autophagic function was impaired in lipid-overloaded human hepatocytes, and the differential effect of PA on autophagy was associated with the duration of PA and the cell type. Under these conditions, the overexpression of SREBP-2 alleviated the inhibited autophagic activity rather than the inhibition of autophagic flux. Consequently, the results indicated that restoration of autophagy dysfunction via the regulation of SREBP-2 may be a potential therapeutic target for the treatment of NAFLD.
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Affiliation(s)
- Chunwei Cheng
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China
| | - Xiaoling Deng
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China
| | - Keshu Xu
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China
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69
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Wu WKK, Zhang L, Chan MTV. Autophagy, NAFLD and NAFLD-Related HCC. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1061:127-138. [PMID: 29956211 DOI: 10.1007/978-981-10-8684-7_10] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) will become a dominant cause of hepatocellular carcinoma (HCC) in the coming decade. Whereas the exact molecular mechanisms underlying the progression from simple steatosis, through steatohepatitis, to HCC remains largely unclear, emerging evidence has supported a central role of defective autophagy in the pathogenesis of NAFLD and its complications. Autophagy not only regulates lipid metabolism and insulin resistance, but also protects hepatocytes from injury and cell death. Nevertheless, in inflammation and tumorigenesis, the role of autophagy is more paradoxical. In NAFLD, defective hepatic autophagy occurs at multiple levels through numerous mechanisms and is causally linked to NAFLD-related HCC. In this chapter, we summarize the regulation and function of autophagy in NAFLD and highlight recent identification of potential pharmacological agents for restoring autophagic flux in NAFLD.
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Affiliation(s)
- William K K Wu
- Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Hong Kong, Hong Kong. .,State Key Laboratory of Digestive Diseases, Department of Medicine & Therapeutics and LKS Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, Hong Kong.
| | - Lin Zhang
- Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Hong Kong, Hong Kong.,State Key Laboratory of Digestive Diseases, Department of Medicine & Therapeutics and LKS Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| | - Matthew T V Chan
- Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Hong Kong, Hong Kong
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70
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Chen B, Zheng YM, Zhang JP. Comparative Study of Different Diets-Induced NAFLD Models of Zebrafish. Front Endocrinol (Lausanne) 2018; 9:366. [PMID: 30026731 PMCID: PMC6041386 DOI: 10.3389/fendo.2018.00366] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 06/18/2018] [Indexed: 12/23/2022] Open
Abstract
Dietary composition has important impact on nonalcoholic fatty liver disease (NAFLD). The purpose of this study was to explore the relationship between NAFLD and major dietary components using zebrafish larvae fed different diets. Zebrafish larvae fed with high cholesterol (HC), high fructose (HF) and extra feeding (EF) diets for 10 days displayed varying degrees steatosis. The incidence and degree of steatosis were the most severe in the EF group. A HC diet severely promoted lipid deposits in the caudal vein. The triglyceride and glucose contents of zebrafish significantly increased in the HF and EF groups compared with the control group. Moreover, the mRNA expression of oxidative stress gene gpx1a, endoplasmic reticulum stress genes ddit3 and grp78, inflammatory genes tnfa, glucose metabolism genes irs2, glut1 and glut2, and lipid metabolism genes cidec, chrebp, ppara and cpt1a were significantly increased in the HF group. The HC diet was associated with upregulation of grp78, and downregulation of irs2, glut1 and glut2. The mRNA expression of lipogenesis and glucose metabolism associated genes were decreased in the EF group. In addition, the autophagy associated genes atg3, atg5, atg7, and atg12, and protein expression of ATG3 and LC3BII were reduced and P62 were elevated in the HC group. We also performed comparative transcriptome analysis of the four groups. A total of 2,492 differentially expressed genes were identified, and 24 statistically significant pathways were enriched in the diet treatment groups. This study extends our understanding of the relationships between diet ingredients and host factors that contribute to the pathogenesis of NAFLD, which may provide new ideas for the treatment of NAFLD.
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71
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Lee AY, Lee JW, Kim JE, Mock HJ, Park S, Kim S, Hong SH, Kim JY, Park EJ, Kang KS, Kim KP, Cho MH. Dihydroceramide is a key metabolite that regulates autophagy and promotes fibrosis in hepatic steatosis model. Biochem Biophys Res Commun 2017; 494:460-469. [PMID: 29066349 DOI: 10.1016/j.bbrc.2017.10.110] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 12/20/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is an increasingly common chronic liver disease worldwide. Sphingolipids are a family of lipids that play essential roles as critical regulators in metabolic disorders. Some sphingolipids are known key factors in metabolic dysfunction. However, the precise effect of dihydroceramide on NAFLD remains unknown. Here, we report how dihydroceramide in autophagosome accumulation activates fibrogenesis in human liver Chang cells treated with free fatty acids (FFA). According to LC/MS lipid profiling, FFA increased the levels of sphingolipids and triacylglycerol (TG). To demonstrate the potential role of dihydroceramide metabolism in autophagy, several sphingolipid synthesis inhibitors were used. Increased dihydroceramide led to impairment of autophagic flux, resulting in increased TG storage in lipid droplets (LD) and upregulated expression of fibrosis markers. Hepatic stellate cells (HSCs, LX-2 cells) were co-cultured with Chang cells to assess the potential fibrogenic response to dihydroceramide, Treatment with rapamycin recovered autophagic flux in Chang cells and fibrogenesis in the co-culture system. Our results identified a critical function of dihydroceramide metabolism in autophagy. It could play an important role in the progression of NAFLD associated with lipid over-accumulation. Therefore, preventing autophagic flux by regulating dihydroceramide could be a potential strategic approach for providing therapy for NAFLD.
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Affiliation(s)
- Ah Young Lee
- Laboratory of Toxicology, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea
| | - Jae Won Lee
- Department of Applied Chemistry, College of Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Ji-Eun Kim
- Laboratory of Toxicology, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea; Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Hyuck Jun Mock
- Department of Applied Chemistry, College of Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Sungjin Park
- Laboratory of Toxicology, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea; Departmentof Pharmacology and Medical Science, Metabolic Diseases and Cell Signaling Laboratory, Research Institute for Medical Sciences, College of Medicine, Chungnam National University, Daejeon 35015, Republic of Korea
| | - Sanghwa Kim
- Laboratory of Toxicology, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea; Division of Basic Radiation Bioscience, Korea Institute of Radiological & Medical Science, Seoul 01812, Republic of Korea
| | - Seong-Ho Hong
- Laboratory of Toxicology, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea; Bio medicine Lab., CKD Research Institute, Yongin 16995, Republic of Korea
| | - Ji-Young Kim
- Laboratory of Toxicology, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea
| | - Eun-Jung Park
- Department of Brain Science, Ajou University School of Medicine, 164, World Cup-ro, Youngtong-gu, Suwon, 16499, Republic of Korea
| | - Kyung-Sun Kang
- Adult Stem Cell Research Center, College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea
| | - Kwang Pyo Kim
- Department of Applied Chemistry, College of Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea.
| | - Myung-Haing Cho
- Laboratory of Toxicology, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea; Graduate School of Convergence Science and Technology, Seoul National University, Suwon 16229, Republic of Korea; Graduate Group of Tumor Biology, Seoul National University, Seoul 08826, Republic of Korea; Advanced Institute of Convergence Technology, Seoul National University, Suwon 16229, Republic of Korea; Institute of GreenBio Science Technology, Seoul National University, Pyeongchang 25354, Republic of Korea.
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72
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Shi H, Wang Q, Yang L, Xie S, Zhu H. IMM-H007, a new therapeutic candidate for nonalcoholic fatty liver disease, improves hepatic steatosis in hamsters fed a high-fat diet. FEBS Open Bio 2017; 7:1379-1391. [PMID: 28904866 PMCID: PMC5586352 DOI: 10.1002/2211-5463.12272] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 07/12/2017] [Accepted: 07/19/2017] [Indexed: 02/06/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD), the most common chronic liver disease in humans, is characterized by the accumulation of triacylglycerols (TGs) in hepatocytes. We tested whether 2′,3′,5′‐tri‐acetyl‐N6‐(3‐hydroxylaniline) adenosine (IMM‐H007) can eliminate hepatic steatosis in hamsters fed a high‐fat diet (HFD), as a model of NAFLD. Compared with HFD‐only controls, IMM‐H007 treatment significantly lowered serum levels of TG, total cholesterol, and free fatty acids (FFAs) in hamsters fed the HFD, with a prominent decrease in levels of serum transaminases and fasting insulin, without affecting fasting glucose levels. Moreover, 1H‐MRI and histopathological analyses revealed that hepatic lipid accumulation and fibrosis were improved by IMM‐H007 treatment. These changes were accompanied by improvement of insulin resistance and oxidative stress, and attenuation of inflammation. IMM‐H007 reduced expression of proteins involved in uptake of hepatic fatty acids and lipogenesis, and increased very low density lipoprotein secretion and expression of proteins responsible for fatty acid oxidation and autophagy. In studies in vivo, IMM‐H007 inhibited fatty acid import into hepatocytes and liver lipogenesis, and concomitantly stimulated fatty acid oxidation, autophagy, and export of hepatic lipids. These data suggest that IMM‐H007 resolves hepatic steatosis in HFD‐fed hamsters by the regulation of lipid metabolism. Thus, IMM‐H007 has therapeutic potential for NAFLD.
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Affiliation(s)
- Huijie Shi
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China.,Department of Pharmacology Shenzhen People's Hospital Second Clinical College Jinan University Shenzhen China
| | - Qingchun Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Liu Yang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Shouxia Xie
- Department of Pharmacology Shenzhen People's Hospital Second Clinical College Jinan University Shenzhen China
| | - Haibo Zhu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
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73
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Meng XH, Chen B, Zhang JP. Intracellular Insulin and Impaired Autophagy in a Zebrafish model and a Cell Model of Type 2 diabetes. Int J Biol Sci 2017; 13:985-995. [PMID: 28924380 PMCID: PMC5599904 DOI: 10.7150/ijbs.19249] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 05/13/2017] [Indexed: 12/16/2022] Open
Abstract
Type 2 diabetes mellitus is characterized by insulin resistance. However, the complete molecular mechanism remains unclear. In this study, zebrafish were fed a long-term high-fat diet to induce type 2 diabetes, which resulted in a higher body weight, body mass index, more lipid vacuoles in liver, increased insulin transcription level in liver, brain and muscle, and high fasting blood glucose in the high-fat diet zebrafish. Oppositely, the transcription levels of insulin substrate-2 and glucose transporter 2 were significantly decreased, indicating insulin signaling pathway and glucose transport impaired in the insulin-targeting tissues. Transcription of the autophagy-related genes, ATG3, ATG4B, ATG5, ATG7, ATG12, and FOXO3, were decreased but autophagy inhibitor gene m-TOR increased, and autophagy-flux was inhibited in liver of the high-fat diet zebrafish. Main of these changes were confirmed in palmitic acid-treated HepG2 cells. Further, in co-immunoprecipitation and subcellular co-localization experiments, the conjunction of preproinsulin with cargo-recognition protein p62 increased, but conjuncts of autophagosome with p62-cargo, lysosomes with p62-cargo, and autolysosomes decreased apparently. Interestingly, lysosomes, autolysosomes and conjuncts of p62-insulin localized at the periphery of palmitic acid-treated cells, the margination of lysosomes may mediate deactivation of proteases activity. These findings suggest that intracellular high-lipid may trigger defective autophagy, defective downstream signaling of insulin and accumulated intracellular preproinsulin, leading to dysregulation of cell homeostasis mechanism, which may be one of reasons involved in insulin-resistance in type 2 diabetes.
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Affiliation(s)
- Xiang-Hui Meng
- Laboratory of pharmacology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Bo Chen
- Laboratory of pharmacology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jing-Pu Zhang
- Laboratory of pharmacology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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74
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Shen Y, Liu Y, Sun T, Yang W. LincRNA-p21 knockdown enhances radiosensitivity of hypoxic tumor cells by reducing autophagy through HIF-1/Akt/mTOR/P70S6K pathway. Exp Cell Res 2017; 358:188-198. [PMID: 28689810 DOI: 10.1016/j.yexcr.2017.06.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/15/2017] [Accepted: 06/22/2017] [Indexed: 02/04/2023]
Abstract
Hypoxic conditions are common in solid tumors and have a significant effect on tumor progression, therapeutic and prognosis. Long noncoding RNAs (lncRNAs) are longer than 200 nucleotides and cannot be translated into proteins, which play important roles in some diseases including cancer. Although previous analysis have showed that long intergenic non-coding RNA (lincRNA)-p21 is hypoxia-responsive and functions as a new regulator of cell cycle, apoptosis and warburg effect in cervical cancer, its biological roles in hypoxic hepatoma and glioma are unknown. In this work, we found that X-ray irradiation or hypoxia treatment elevated lincRNA-p21 expression in SMMC7721 hepatoma and U251MG glioma cells. Knockdown of lincRNA-p21 induced G2/M phase arrest, promoted apoptosis, decreased cell proliferation and motility, and reduced autophagy through HIF-1/Akt/mTOR/P70S6K pathway in hypoxic tumor cells. Our results delineated a novel mechanism of lincRNA-p21 in enhancing hypoxic tumor cell radiosensitivity, which might provide valuable targets for radiation therapy for solid tumors, such as hepatoma and glioma.
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Affiliation(s)
- Yueming Shen
- Department of Radiobiology, School of Radiological Medicine and Protection, Medical College of Soochow University, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu 215123, China
| | - Yingying Liu
- Department of Radiobiology, School of Radiological Medicine and Protection, Medical College of Soochow University, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu 215123, China
| | - Ting Sun
- Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, China.
| | - Wei Yang
- Department of Radiobiology, School of Radiological Medicine and Protection, Medical College of Soochow University, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu 215123, China.
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75
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ER Stress and Autophagy in Obesity and Nonalcoholic Fatty Liver Disease. CURRENT PATHOBIOLOGY REPORTS 2017. [DOI: 10.1007/s40139-017-0145-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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76
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Li M, Sharma A, Yin C, Tan X, Xiao Y. Metformin ameliorates hepatic steatosis and improves the induction of autophagy in HFD‑induced obese mice. Mol Med Rep 2017; 16:680-686. [PMID: 28560428 PMCID: PMC5482143 DOI: 10.3892/mmr.2017.6637] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 02/20/2017] [Indexed: 12/20/2022] Open
Abstract
The present study aimed to investigate the effect of metformin on the induction of autophagy in the liver and adipose tissues of a mouse model of obesity. C57BL/6J mice were fed a high‑fat diet (HFD) for 12 weeks to induce obesity‑associated hepatic steatosis, and treated with metformin (150 mg/kg/d) by intraperitoneal injection for the final 4 weeks of HFD feeding. Body weight was recorded weekly, and the food intake of the mice was recorded daily during the treatment period. Liver and adipose tissues were harvested for histological and molecular analyses. The results revealed that metformin significantly reduced body weight without altering food intake in the HFD mice, particularly in the epididymal white adipose tissue (eWAT). Metformin treatment ameliorated HFD‑induced hepatic steatosis and serum levels of triglycerides, which was consistent with a marked increase in the expression levels of microtubule‑associated protein 1 light chain 3 (LC3) and AMP‑activated protein kinase (AMPK) in the liver following metformin treatment. However, metformin suppressed the expression of LC3 in the eWAT without altering the expression of AMPK, compared with that in the HFD mice. In conclusion, metformin reduced the body weight and hepatic steatosis of the HFD‑induced obese mice, without altering food intake. The effects of metformin treatment may be attributable to the improved induction of hepatic autophagy and the inhibited induction of adipose tissue autophagy.
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Affiliation(s)
- Min Li
- Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Antara Sharma
- Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Chunyan Yin
- Pediatrics Department, 2nd Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Xinrui Tan
- Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Yanfeng Xiao
- Pediatrics Department, 2nd Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
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77
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Gual P, Gilgenkrantz H, Lotersztajn S. [Autophagy in chronic liver diseases: a friend rather than a foe?]. Med Sci (Paris) 2017; 33:252-259. [PMID: 28367811 DOI: 10.1051/medsci/20173303011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Within recycling damaged cell components, autophagy maintains cell homeostasis. Thus, it has been anticipated that autophagy would play an essential role in the pathogenesis of chronic liver diseases. Alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) are the most prevalent chronic liver diseases in Western countries, sharing common histopathologic features and a common disease progression. In this review, we discuss the role of autophagy at different stages of NAFLD and ALD as well as in liver regeneration and hepatocarcinogenesis.
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Affiliation(s)
- Philippe Gual
- Inserm, U1065, C3M, Team 8 "Hepatic complications in obesity", Nice, France - Université Nice Côte d'Azur, Inserm, C3M, Nice, France
| | - Hélène Gilgenkrantz
- Institut Cochin, Inserm, U1016, CNRS UMR 8104, université Paris-Descartes, Paris, France
| | - Sophie Lotersztajn
- Inserm-U1149, CNRS-ERL8252, Centre de recherche sur l'inflammation, Paris, France - Sorbonne Paris Cité, Laboratoire d'excellence Inflamex, faculté de médecine, site Xavier Bichat, université Paris Diderot, Paris, France
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78
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Liu C, Liao JZ, Li PY. Traditional Chinese herbal extracts inducing autophagy as a novel approach in therapy of nonalcoholic fatty liver disease. World J Gastroenterol 2017; 23:1964-1973. [PMID: 28373762 PMCID: PMC5360637 DOI: 10.3748/wjg.v23.i11.1964] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 12/23/2016] [Accepted: 01/18/2017] [Indexed: 02/07/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver diseases around the world due to the modern sedentary and food-abundant lifestyle, which is characterized by excessive fat accumulation in the liver related with causes other than alcohol abuse. It is widely acknowledged that insulin resistance, dysfunctional lipid metabolism, endoplasmic reticulum stress, oxidative stress, inflammation, and apoptosis/necrosis may all contribute to NAFLD. Autophagy is a protective self-digestion of intracellular organelles, including lipid droplets (lipophagy), in response to stress to maintain homeostasis. Lipophagy is another pathway for lipid degradation besides lipolysis. It is reported that impaired autophagy also contributes to NAFLD. Some studies have suggested that the histological characteristics of NAFLD (steatosis, lobular inflammation, and peri-sinusoid fibrosis) might be improved by treatment with traditional Chinese herbal extracts, while autophagy may be induced. This review will provide insights into the characteristics of autophagy in NAFLD and the related role/mechanisms of autophagy induced by traditional Chinese herbal extracts such as resveratrol, Lycium barbarum polysaccharides, dioscin, bergamot polyphenol fraction, capsaicin, and garlic-derived S-allylmercaptocysteine, which may inhibit the progression of NAFLD. Regulation of autophagy/lipophagy with traditional Chinese herbal extracts may be a novel approach for treating NAFLD, and the molecular mechanisms should be elucidated further in the near future.
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79
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Gual P, Gilgenkrantz H, Lotersztajn S. Autophagy in chronic liver diseases: the two faces of Janus. Am J Physiol Cell Physiol 2017; 312:C263-C273. [DOI: 10.1152/ajpcell.00295.2016] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 11/22/2016] [Accepted: 11/22/2016] [Indexed: 02/07/2023]
Abstract
Alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) are the leading causes of cirrhosis and increase the risk of hepatocellular carcinoma and liver-related death. ALD and NAFLD share common pathogenic features extending from isolated steatosis to steatohepatitis and steatofibrosis, which can progress to cirrhosis and hepatocellular carcinoma. The pathophysiological mechanisms of the progression of NAFLD and ALD are complex and still unclear. Important links between the regulation of autophagy (macroautophagy and chaperone-mediated autophagy) and chronic liver diseases have been reported. Autophagy may protect against steatosis and progression to steatohepatitis by limiting hepatocyte injury and reducing M1 polarization, as well as promoting liver regeneration. Its role in fibrosis and hepatocarcinogenesis is more complex. It has pro- and antifibrogenic properties depending on the hepatic cell type concerned, and beneficial and deleterious effects on hepatocarcinogenesis at initiating and late phases, respectively. This review summarizes the latest advances on the role of autophagy in different stages of fatty liver disease progression and describes its divergent and cell-specific effects during chronic liver injury.
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Affiliation(s)
- Philippe Gual
- Inserm-U1065, C3M, Team 8 “Hepatic complications in obesity,” Nice, France
- Université Nice Côte d’Azur, Inserm, C3M, Nice, France
| | - Hélène Gilgenkrantz
- Institut Cochin, Inserm-U1016, CNRS UMR 8104, Université Paris-Descartes, Paris, France
| | - Sophie Lotersztajn
- Inserm-U1149, CNRS-ERL8252, Centre de Recherche sur l'Inflammation, Paris, France; and
- Sorbonne Paris Cité, Laboratoire d'Excellence Inflamex, Faculté de Médecine, Site Xavier Bichat, Université Paris Diderot, Paris, France
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80
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Massart J, Begriche K, Moreau C, Fromenty B. Role of nonalcoholic fatty liver disease as risk factor for drug-induced hepatotoxicity. J Clin Transl Res 2017; 3:212-232. [PMID: 28691103 PMCID: PMC5500243 DOI: 10.18053/jctres.03.2017s1.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Obesity is often associated with nonalcoholic fatty liver disease (NAFLD), which refers to a large spectrum of hepatic lesions including fatty liver, nonalcoholic steatohepatitis (NASH) and cirrhosis. Different investigations showed or suggested that obesity and NAFLD are able to increase the risk of hepatotoxicity of different drugs. Some of these drugs could induce more frequently an acute hepatitis in obese individuals whereas others could worsen pre-existing NAFLD. AIM The main objective of the present review was to collect the available information regarding the role of NAFLD as risk factor for drug-induced hepatotoxicity. For this purpose, we performed a data-mining analysis using different queries including drug-induced liver injury (or DILI), drug-induced hepatotoxicity, fatty liver, nonalcoholic fatty liver disease (or NAFLD), steatosis and obesity. The main data from the collected articles are reported in this review and when available, some pathophysiological hypotheses are put forward. RELEVANCE FOR PATIENTS Drugs that could pose a potential risk in obese patients include compounds belonging to different pharmacological classes such as acetaminophen, halothane, methotrexate, rosiglitazone, stavudine and tamoxifen. For some of these drugs, experimental investigations in obese rodents confirmed the clinical observations and unveiled different pathophysiological mechanisms which could explain why these pharmaceuticals are particularly hepatotoxic in obesity and NAFLD. Other drugs such as pentoxifylline, phenobarbital and omeprazole might also pose a risk but more investigations are required to determine whether this risk is significant or not. Because obese people often take several drugs for the treatment of different obesity-related diseases such as type 2 diabetes, hyperlipidemia and coronary heart disease, it is urgent to identify the main pharmaceuticals that can cause acute hepatitis on a fatty liver background or induce NAFLD worsening.
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Affiliation(s)
- Julie Massart
- Department of Molecular Medicine and Surgery, Karolinska University Hospital, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | | | - Caroline Moreau
- INSERM, U991, Université de Rennes 1, Rennes, France.,Service de Biochimie et Toxicologie, CHU Pontchaillou, Rennes, France
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81
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Tubbs E, Rieusset J. Metabolic signaling functions of ER-mitochondria contact sites: role in metabolic diseases. J Mol Endocrinol 2017; 58:R87-R106. [PMID: 27965371 DOI: 10.1530/jme-16-0189] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 12/13/2016] [Indexed: 12/16/2022]
Abstract
Beyond the maintenance of cellular homeostasis and the determination of cell fate, ER-mitochondria contact sites, defined as mitochondria-associated membranes (MAM), start to emerge as an important signaling hub that integrates nutrient and hormonal stimuli and adapts cellular metabolism. Here, we summarize the established structural and functional features of MAM and mainly focus on the latest breakthroughs highlighting a crucial role of organelle crosstalk in the control of metabolic homeostasis. Lastly, we discuss recent studies that have revealed the importance of MAM in not only metabolic diseases but also in other pathologies with disrupted metabolism, shedding light on potential common molecular mechanisms and leading hopefully to novel treatment strategies.
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Affiliation(s)
- Emily Tubbs
- Department of Clinical SciencesLund University Diabetes Centre, Malmö, Sweden
| | - Jennifer Rieusset
- INSERM UMR-1060CarMeN Laboratory, Lyon 1 University, INRA U1235, INSA of Lyon, Charles Merieux Lyon-Sud medical Universities, Lyon, France
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82
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Rosa-Caldwell ME, Lee DE, Brown JL, Brown LA, Perry RA, Greene ES, Carvallo Chaigneau FR, Washington TA, Greene NP. Moderate physical activity promotes basal hepatic autophagy in diet-induced obese mice. Appl Physiol Nutr Metab 2017; 42:148-156. [DOI: 10.1139/apnm-2016-0280] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Obesity is a known risk factor for the development of hepatic disease; obesity-induced fatty liver can lead to inflammation, steatosis, and cirrhosis and is associated with degeneration of the mitochondria. Lifestyle interventions such as physical activity may ameliorate this condition. The purpose of this study was to investigate regulation of mitochondrial and autophagy quality control in liver following Western diet-induced obesity and voluntary physical activity. Eight-week-old C57BL/6J mice were fed a Western diet (WD) or normal chow (NC, control) for 4 weeks; afterwards, groups were divided into voluntary wheel running (VWR) or sedentary (SED) conditions for an additional 4 weeks. WD-SED animals had a median histology score of 2, whereas WD-VWR was not different from NC groups (median score 1). There was no difference in mRNA of inflammatory markers Il6 and Tnfa in WD animals. WD animals had 50% lower mitochondrial content (COX IV and Cytochrome C proteins), 50% lower Pgc1a mRNA content, and reduced content of mitochondrial fusion and fission markers. Markers of autophagy were increased in VWR animals, regardless of obesity, as measured by 50% greater LC3-II/I ratio and 40% lower p62 protein content. BNIP3 protein content was 30% less in WD animals compared with NC animals, regardless of physical activity. Diet-induced obesity results in derangements in mitochondrial quality control that appear to occur prior to the onset of hepatic inflammation. Moderate physical activity appears to enhance basal autophagy in the liver; increased autophagy may provide protection from hepatic fat accumulation.
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Affiliation(s)
- Megan E. Rosa-Caldwell
- Integrative Muscle Metabolism Laboratory, Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR 72701, USA
| | - David E. Lee
- Integrative Muscle Metabolism Laboratory, Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR 72701, USA
| | - Jacob L. Brown
- Integrative Muscle Metabolism Laboratory, Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR 72701, USA
| | - Lemuel A. Brown
- Exercise Muscle Biology Laboratory, Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR 72701, USA
| | - Richard A. Perry
- Exercise Muscle Biology Laboratory, Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR 72701, USA
| | - Elizabeth S. Greene
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - Francisco R. Carvallo Chaigneau
- California Animal Health and Food Safety Laboratory, University of California-Davis School of Veterinary Medicine, Davis, CA 95616, USA
| | - Tyrone A. Washington
- Exercise Muscle Biology Laboratory, Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR 72701, USA
| | - Nicholas P. Greene
- Integrative Muscle Metabolism Laboratory, Human Performance Laboratory, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR 72701, USA
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83
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Rieusset J. Endoplasmic reticulum-mitochondria calcium signaling in hepatic metabolic diseases. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:865-876. [PMID: 28064001 DOI: 10.1016/j.bbamcr.2017.01.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 12/21/2016] [Accepted: 01/02/2017] [Indexed: 02/07/2023]
Abstract
The liver plays a central role in glucose homeostasis, and both metabolic inflexibility and insulin resistance predispose to the development of hepatic metabolic diseases. Mitochondria and endoplasmic reticulum (ER), which play a key role in the control of hepatic metabolism, also interact at contact points defined as mitochondria-associated membranes (MAM), in order to exchange metabolites and calcium (Ca2+) and regulate cellular homeostasis and signaling. Here, we overview the role of the liver in the control of glucose homeostasis, mainly focusing on the independent involvement of mitochondria, ER and Ca2+ signaling in both healthy and pathological contexts. Then we focus on recent data highlighting MAM as important hubs for hormone and nutrient signaling in the liver, thus adapting mitochondria physiology and cellular metabolism to energy availability. Lastly, we discuss how chronic ER-mitochondria miscommunication could participate to hepatic metabolic diseases, pointing MAM interface as a potential therapeutic target for metabolic disorders. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.
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Affiliation(s)
- Jennifer Rieusset
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1397, F-69921 Oullins, France.
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84
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He Q, Mei D, Sha S, Fan S, Wang L, Dong M. ERK-dependent mTOR pathway is involved in berberine-induced autophagy in hepatic steatosis. J Mol Endocrinol 2016; 57:251-260. [PMID: 27658958 DOI: 10.1530/jme-16-0139] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 09/21/2016] [Indexed: 12/27/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a burgeoning health problem and is considered as a hepatic manifestation of metabolic syndrome. Increasing evidence demonstrates that berberine (BBR), a natural plant alkaloid, is beneficial for obesity-associated NAFLD. However, the mechanisms about how BBR improves hepatic steatosis remain uncertain. Recently, some reports revealed that enhanced autophagy could decrease hepatic lipid accumulation. In this study, we first established a high-fed diet (HFD) mice model and oleate-palmitate-induced lipotoxicity hepatocytes to explore the association among BBR, autophagy and hepatic steatosis. Our data demonstrated that BBR had profound effects on improving hepatic lipid accumulation both in vivo and in vitro, and led to high autophagy flux. The molecular alterations proceeding these changes were characterized by inhibition of the ERK/mTOR pathway. These findings suggest an important mechanism for the positive effects of BBR on hepatic steatosis, and may provide new evidence for the clinical use of BBR in NAFLD.
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Affiliation(s)
- Qin He
- Department of Endocrine and MetabolismQilu Hospital of Shandong University, Shandong University, Ji'nan, Shandong, China
| | - Dan Mei
- Department of Endocrine and MetabolismQilu Hospital of Shandong University, Shandong University, Ji'nan, Shandong, China
| | - Sha Sha
- Department of Endocrine and MetabolismQilu Hospital of Shandong University, Shandong University, Ji'nan, Shandong, China
| | - Shanshan Fan
- Department of Endocrine and MetabolismQilu Hospital of Shandong University, Shandong University, Ji'nan, Shandong, China
| | - Lin Wang
- Department of Endocrine and MetabolismJiaxiang People's Hospital, Ji'ning, Shandong, China
| | - Ming Dong
- Department of Endocrine and MetabolismQilu Hospital of Shandong University, Shandong University, Ji'nan, Shandong, China
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85
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Gong LL, Li GR, Zhang W, Liu H, Lv YL, Han FF, Wan ZR, Shi MB, Liu LH. Akebia Saponin D Decreases Hepatic Steatosis through Autophagy Modulation. J Pharmacol Exp Ther 2016; 359:392-400. [DOI: 10.1124/jpet.116.236562] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 09/20/2016] [Indexed: 01/01/2023] Open
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86
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Taniguchi K, Yamachika S, He F, Karin M. p62/SQSTM1-Dr. Jekyll and Mr. Hyde that prevents oxidative stress but promotes liver cancer. FEBS Lett 2016; 590:2375-97. [PMID: 27404485 DOI: 10.1002/1873-3468.12301] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/08/2016] [Accepted: 07/09/2016] [Indexed: 12/17/2022]
Abstract
p62/SQSTM1 is a multifunctional signaling hub and autophagy adaptor with many binding partners, which allow it to activate mTORC1-dependent nutrient sensing, NF-κB-mediated inflammatory responses, and the NRF2-activated antioxidant defense. p62 recognizes polyubiquitin chains via its C-terminal domain and binds to LC3 via its LIR motif, thereby promoting the autophagic degradation of ubiquitinated cargos. p62 accumulates in many human liver diseases, including nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC), where it is a component of Mallory-Denk bodies and intracellular hyaline bodies. Chronic p62 elevation contributes to HCC development by preventing oncogene-induced senescence and death of cancer-initiating cells and enhancing their proliferation. In this review, we discuss p62-mediated signaling pathways and their roles in liver pathophysiology, especially NASH and HCC.
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Affiliation(s)
- Koji Taniguchi
- Laboratory of Gene Regulation and Signal Transduction, Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, USA.,Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Microbiology and Immunology, Keio University School of Medicine, Tokyo, Japan
| | - Shinichiro Yamachika
- Laboratory of Gene Regulation and Signal Transduction, Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, USA
| | - Feng He
- Laboratory of Gene Regulation and Signal Transduction, Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, USA
| | - Michael Karin
- Laboratory of Gene Regulation and Signal Transduction, Departments of Pharmacology and Pathology, University of California San Diego, La Jolla, CA, USA
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87
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Regulation of autophagy by mitochondrial phospholipids in health and diseases. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:114-129. [PMID: 27502688 DOI: 10.1016/j.bbalip.2016.08.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 07/28/2016] [Accepted: 08/04/2016] [Indexed: 12/16/2022]
Abstract
Autophagy is an evolutionarily conserved mechanism that maintains nutrient homeostasis by degrading protein aggregates and damaged organelles. Autophagy is reduced in aging, which is implicated in the pathogenesis of aging-related diseases, including cancers, obesity, type 2 diabetes, cardiovascular diseases, and neurodegenerative diseases. Mitochondria-derived phospholipids cardiolipin, phosphatidylethanolamine, and phosphatidylglycerol are critical throughout the autophagic process, from initiation and phagophore formation to elongation and fusion with endolysosomal vesicles. Cardiolipin is also required for mitochondrial fusion and fission, an important step in isolating dysfunctional mitochondria for mitophagy. Furthermore, genetic screen in yeast has identified a surprising role for cardiolipin in regulating lysosomal function. Phosphatidylethanolamine plays a pivotal role in supporting the autophagic process, including autophagosome elongation as part of lipidated Atg8/LC3. An emerging role for phosphatidylglycerol in AMPK and mTORC1 signaling as well as mitochondrial fission may provide the first glimpse into the function of phosphatidylglycerol apart from being a precursor for cardiolipin. This review examines the effects of manipulating phospholipids on autophagy and mitophagy in health and diseases, as well as current limitations in the field. This article is part of a Special Issue entitled: Lipids of Mitochondria edited by Guenther Daum.
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88
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de Luxán-Delgado B, Potes Y, Rubio-González A, Caballero B, Solano JJ, Fernández-Fernández M, Bermúdez M, Rodrigues Moreira Guimarães M, Vega-Naredo I, Boga JA, Coto-Montes A. Melatonin reduces endoplasmic reticulum stress and autophagy in liver of leptin-deficient mice. J Pineal Res 2016; 61:108-23. [PMID: 27090356 DOI: 10.1111/jpi.12333] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 04/12/2016] [Indexed: 12/17/2022]
Abstract
The sedentary lifestyle of modern society along with the high intake of energetic food has made obesity a current worldwide health problem. Despite great efforts to study the obesity and its related diseases, the mechanisms underlying the development of these diseases are not well understood. Therefore, identifying novel strategies to slow the progression of these diseases is urgently needed. Experimental observations indicate that melatonin has an important role in energy metabolism and cell signalling; thus, the use of this molecule may counteract the pathologies of obesity. In this study, wild-type and obese (ob/ob) mice received daily intraperitoneal injections of melatonin at a dose of 500 μg/kg body weight for 4 weeks, and the livers of these mice were used to evaluate the oxidative stress status, proteolytic (autophagy and proteasome) activity, unfolded protein response, inflammation and insulin signalling. Our results show, for the first time, that melatonin could significantly reduce endoplasmic reticulum stress in leptin-deficient obese animals and ameliorate several symptoms that characterize this disease. Our study supports the potential of melatonin as a therapeutic treatment for the most common type of obesity and its liver-associated disorders.
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Affiliation(s)
- Beatriz de Luxán-Delgado
- Department of Morphology and Cellular Biology, Faculty of Medicine, University of Oviedo, Oviedo, Spain
| | - Yaiza Potes
- Department of Morphology and Cellular Biology, Faculty of Medicine, University of Oviedo, Oviedo, Spain
| | - Adrian Rubio-González
- Department of Morphology and Cellular Biology, Faculty of Medicine, University of Oviedo, Oviedo, Spain
| | - Beatriz Caballero
- Department of Morphology and Cellular Biology, Faculty of Medicine, University of Oviedo, Oviedo, Spain
| | | | | | | | - Marcela Rodrigues Moreira Guimarães
- Department of Morphology and Cellular Biology, Faculty of Medicine, University of Oviedo, Oviedo, Spain
- Neurology, Laboratory of Nutritional Investigation and Degenerative-Chronic Diseases (LINDCD), Federal University of Rio de Janeiro State - UNIRIO, Rio de Janeiro, Brazil
| | - Ignacio Vega-Naredo
- Department of Morphology and Cellular Biology, Faculty of Medicine, University of Oviedo, Oviedo, Spain
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Cantanhede, Portugal
| | - José Antonio Boga
- Microbiology Department, Hospital Universitario Central de Asturias, Asturias, Oviedo, Spain
| | - Ana Coto-Montes
- Department of Morphology and Cellular Biology, Faculty of Medicine, University of Oviedo, Oviedo, Spain
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Xu YY, Ge J, Zhang MH, Sun WJ, Zhang J, Yu PL, Zheng YF, Yang J, Zhu XQ. Intravenous Administration of Multiwalled Carbon Nanotubes Aggravates High-Fat Diet-Induced Nonalcoholic Steatohepatitis in Sprague Dawley Rats. Int J Toxicol 2016; 35:634-643. [PMID: 27306319 DOI: 10.1177/1091581816653363] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Multiwalled carbon nanotubes (MWCNTs) have been explored in pharmaceutical applications such as tumor targeting and delivery of drugs, in which MWCNTs are given through intravenous injection. However, the biosafety of MWCNTs is of concern for such application. Therefore, in the current study, we used a fatty liver model to investigate the possible toxicity of MWCNTs to the liver, as MWCNTs were retained mainly in the liver of mice after intravenous injection. Male Sprague Dawley rats were used to generate the fatty liver model, and the effects of intravenous administration of MWCNTs on fatty liver were studied. Hematoxylin and eosin staining for hepatocellular anatomy and Masson trichrome staining for hepatic fibrosis were conducted. Histologically, MWCNTs aggravated steatohepatitis with higher nonalcoholic fatty liver disease scores. Analysis of liver injury markers indicated that MWCNTs administration resulted in chronic hepatitis, along with increased liver fat and altered liver oxidation, including the increase of P6 protein and the depletion of glutathione. In conclusion, our results suggest that MWCNTs can aggravate nonalcoholic steatohepatitis in Sprague Dawley rats, and oxidative injury may be involved in this process.
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Affiliation(s)
- Yu-Ying Xu
- Department of Toxicology, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
| | - Juan Ge
- Department of Toxicology, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
| | - Mo-Han Zhang
- Department of Toxicology, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
| | - Wen-Jie Sun
- Department of Toxicology, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jun Zhang
- Department of Toxicology, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
| | - Pei-Lin Yu
- Department of Toxicology, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yi-Fan Zheng
- Department of Toxicology, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jun Yang
- Department of Toxicology, School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, China
- Collaborative Innovation Center for the Diagnosis and Treatment of Infectious Diseases, National Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xin-Qiang Zhu
- Department of Toxicology, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China
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90
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Kim S, Park S, Kim B, Kwon J. Toll-like receptor 7 affects the pathogenesis of non-alcoholic fatty liver disease. Sci Rep 2016; 6:27849. [PMID: 27279075 PMCID: PMC4899790 DOI: 10.1038/srep27849] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 05/25/2016] [Indexed: 12/20/2022] Open
Abstract
Recently, a possible link between toll-like receptor 7 (TLR7) and liver disease was suggested, although it was limited to fibrosis. Based on this report, we investigated whether TLR7 has a pivotal role in non-alcoholic fatty liver disease (NAFLD). The TLR7 signaling pathway, which is activated by imiquimod (TLR7 ligand) naturally, induced autophagy and released insulin-like growth factor 1 (IGF-1) into medium from hepatocytes. Lipid accumulation induced by unsaturated fatty acid (UFA; arachidonic acid:oleic acid = 1:1) in hepatocytes, was attenuated in TLR7 and autophagy activation. Interestingly, TLR7 activation attenuated UFA-induced lipid peroxidation products, such as malondialdehyde (MDA) and 4-Hydroxy-2-Nonenal (4-HNE). To clarify a possible pathway between TLR7 and lipid peroxidation, we treated hepatocytes with MDA and 4-HNE. MDA and 4-HNE induced 2-folds lipid accumulation in UFA-treated hepatocytes via blockade of the TLR7 signaling pathway's IGF-1 release compared to only UFA-treated hepatocytes. In vivo experiments carried out with TLR7 knockout mice produced results consistent with in vitro experiments. In conclusion, TLR7 prevents progression of NAFLD via induced autophagy and released IGF-1 from liver. These findings suggest a new therapeutic strategy for the treatment of NAFLD.
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Affiliation(s)
- Sokho Kim
- Department of Laboratory Animal Medicine, Chonbuk National University, 79 Gobongro, Iksan, 54596, Republic of Korea
| | - Surim Park
- Laboratory of Pathology, College of Veterinary Medicine, Chonbuk National University, 79 Gobongro, Iksan, 54596, Republic of Korea
| | - Bumseok Kim
- Laboratory of Pathology, College of Veterinary Medicine, Chonbuk National University, 79 Gobongro, Iksan, 54596, Republic of Korea
| | - Jungkee Kwon
- Department of Laboratory Animal Medicine, Chonbuk National University, 79 Gobongro, Iksan, 54596, Republic of Korea
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91
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Abstract
Nonalcoholic fatty liver disease (NAFLD) has gained importance in recent decades due to drastic changes in diet, especially in Western countries. NAFLD occurs as a spectrum from simple hepatic steatosis, steatohepatitis to cirrhosis, and even hepatocellular carcinoma. Although the molecular mechanisms underlying the development of NAFLD have been intensively investigated, many issues remain to be resolved. Autophagy is a cell survival mechanism for disposing of excess or defective organelles, and has become a hot spot for research. Recent studies have revealed that autophagy is linked to the development of NAFLD and regulation of autophagy has therapeutic potential. Autophagy reduces intracellular lipid droplets by enclosing them and fusing with lysosomes for degradation. Furthermore, autophagy is involved in attenuating inflammation and liver injury. However, autophagy is regarded as a double-edged sword, as it may also affect adipogenesis and adipocyte differentiation. Moreover, it is unclear as to whether autophagy protects the body from injury or causes diseases and even death, and the association between autophagy and NAFLD remains controversial. This review is intended to discuss, comment, and outline the progress made in this field and establish the possible molecular mechanism involved.
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Affiliation(s)
- Yuqing Mao
- Department of Gastroenterology and Hepatology, Jinshan Hospital of Fudan University, Shanghai, People's Republic of China
| | - Fujun Yu
- Department of Gastroenterology and Hepatology, Jinshan Hospital of Fudan University, Shanghai, People's Republic of China
| | - Jianbo Wang
- Department of Gastroenterology and Hepatology, The Central Hospital of Lishui City, Wenzhou Medical University, Zhejiang, People's Republic of China
| | - Chuanyong Guo
- Department of Gastroenterology and Hepatology, Shanghai Tenth People's Hospital, Tongji University, Shanghai, People's Republic of China
| | - Xiaoming Fan
- Department of Gastroenterology and Hepatology, Jinshan Hospital of Fudan University, Shanghai, People's Republic of China
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92
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Xiong J, Wang K, He J, Zhang G, Zhang D, Chen F. TFE3 Alleviates Hepatic Steatosis through Autophagy-Induced Lipophagy and PGC1α-Mediated Fatty Acid β-Oxidation. Int J Mol Sci 2016; 17:387. [PMID: 26999124 PMCID: PMC4813243 DOI: 10.3390/ijms17030387] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 03/06/2016] [Accepted: 03/07/2016] [Indexed: 02/06/2023] Open
Abstract
Autophagy flux deficiency is closely related to the development of hepatic steatosis. Transcription factor E3 (TFE3) is reported to be a crucial gene that regulates autophagy flux and lysosome function. Therefore, we investigated the role of TFE3 in a cell model of hepatic steatosis. We constructed L02 hepatocyte lines that stably over-expressed or knocked down the expression of TFE3. Subsequently, the effects of TFE3 on hepatocellular lipid metabolism were determined by autophagy flux assay, lipid oil red O (ORO) staining, immunofluorescence staining, and mitochondrial β-oxidation assessment. Finally, we analyzed whether peroxisome proliferative activated receptor gamma coactivator 1α (PGC1α) was the potential target gene of TFE3 in the regulation of hepatic steatosis using a chromatin immunoprecipitation (CHIP) assay and a luciferase reporter system. We found that overexpression of TFE3 markedly alleviated hepatocellular steatosis. On the contrary, downregulation of TFE3 resulted in an aggravated steatosis. The mechanistic studies revealed that the TFE3-manipulated regulatory effects on hepatocellular steatosis are dependent on autophagy-induced lipophagy and PGC1α-mediated fatty acid β-oxidation because blocking these pathways with an Atg5 small interfering RNA (siRNA) or PGC1α siRNA dramatically blunted the TFE3-mediated regulation of steatosis. In conclusion, TFE3 gene provides a novel insight into the treatment of hepatic steatosis and other metabolic disease.
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Affiliation(s)
- Jie Xiong
- Department of Endocrinology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China.
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China.
| | - Kezhou Wang
- Department of Pathology and Pathophysiology, Dalian Medical University, Dalian 116044, China.
| | - Jiangping He
- Department of Endocrinology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China.
| | - Guangya Zhang
- Department of Endocrinology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China.
| | - Dandan Zhang
- Department of Endocrinology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China.
| | - Fengling Chen
- Department of Endocrinology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, China.
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93
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Liao N, Pan F, Wang Y, Zheng Y, Xu B, Chen W, Gao Y, Cai Z, Liu X, Liu J. Adipose tissue-derived stem cells promote the reversion of non-alcoholic fatty liver disease: An in vivo study. Int J Mol Med 2016; 37:1389-96. [PMID: 26986083 DOI: 10.3892/ijmm.2016.2528] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 03/04/2016] [Indexed: 11/06/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most common cause of liver injury and seriously affects human health. In the present study, we aimed to investigate whether adipose tissue-derived stem cell (ADSC) transplantation in combination with dietary modification was capable of reversing the progression of NAFLD. After establishing a rat model of NAFLD by feeding them a high-fat diet (HFD), ADSCs were transplanted via the portal vein into rats with HFD-induced NAFLD, and simultaneously fed a modified diet. Thereafter, gross liver morphology, the hepatosomatic (HSI) index and indicators of liver function, including alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) were evaluated. Subsequently, the serum levels of total cholesterol (TC), triglycerides (TGs) and fatty acids (FAs) were also assayed. Furthermore, H&E and oil red O staining were used to confirm the pathological effects of NAFLD in the rat livers. Although dietary modification alone caused liver function to recover, ADSC transplantation in combination with dietary modification further decreased the HSI index, the serum levels of ALT, TBIL, TC, TGs, FAs, reduced lipid accumulation to normal levels, and reversed the hepatic pathological changes in the rat livers. Taken together, these findings suggest that ADSC transplantation assists in the reversion of NAFLD by improving liver function and promoting lipid metabolism, thereby exerting hepatoprotective effects. Thus, we suggest that ADSC transplantation is a promising, potential therapeutic strategy for NAFLD treatment.
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Affiliation(s)
- Naishun Liao
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
| | - Fan Pan
- Department of Hepatobiliary Surgery, Fuzong Clinical College, Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
| | - Yingchao Wang
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
| | - Youshi Zheng
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
| | - Bo Xu
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
| | - Wenwei Chen
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
| | - Yunzhen Gao
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
| | - Zhixiong Cai
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
| | - Xiaolong Liu
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
| | - Jingfeng Liu
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian 350025, P.R. China
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94
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Quercetin Alleviates High-Fat Diet-Induced Oxidized Low-Density Lipoprotein Accumulation in the Liver: Implication for Autophagy Regulation. BIOMED RESEARCH INTERNATIONAL 2015; 2015:607531. [PMID: 26697490 PMCID: PMC4678061 DOI: 10.1155/2015/607531] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 10/23/2015] [Accepted: 11/04/2015] [Indexed: 12/16/2022]
Abstract
A growing body of evidence has indicated that high-fat diet-induced nonalcoholic fatty liver disease is usually accompanied by oxidized low-density lipoprotein (ox-LDL) deposited in the liver. The current study aimed to investigate the effect of quercetin on high-fat diet-induced ox-LDL accumulation in the liver and to explore the potential underlying mechanisms. The results demonstrate that quercetin supplementation for 24 weeks significantly alleviated high-fat diet-induced liver damage and reduced hepatic cholesterol and ox-LDL level. Quercetin notably inhibited both mRNA and protein expression of CD36 (reduced by 53% and 71%, resp.) and MSR1 (reduced by 25% and 45%, resp.), which were upregulated by high-fat diet. The expression of LC3II was upregulated by 2.4 times whereas that of p62 and mTOR was downregulated by 57% and 63% by quercetin treatment. Therefore, the significantly improved autophagy lysosomal degradation capacity for ox-LDL may be implicated in the hepatoprotective effect of quercetin; scavenger receptors mediated ox-LDL uptake might also be involved.
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95
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Molecular mechanisms of fatty liver in obesity. Front Med 2015; 9:275-87. [PMID: 26290284 DOI: 10.1007/s11684-015-0410-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Accepted: 05/25/2015] [Indexed: 12/17/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) covers a spectrum of liver disorders ranging from simple steatosis to advanced pathologies, including nonalcoholic steatohepatitis and cirrhosis. NAFLD significantly contributes to morbidity and mortality in developed societies. Insulin resistance associated with central obesity is the major cause of hepatic steatosis, which is characterized by excessive accumulation of triglyceride-rich lipid droplets in the liver. Accumulating evidence supports that dysregulation of adipose lipolysis and liver de novo lipogenesis (DNL) plays a key role in driving hepatic steatosis. In this work, we reviewed the molecular mechanisms responsible for enhanced adipose lipolysis and increased hepatic DNL that lead to hepatic lipid accumulation in the context of obesity. Delineation of these mechanisms holds promise for developing novel avenues against NAFLD.
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96
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Kim SH, Wu SY, Baek JI, Choi SY, Su Y, Flynn CR, Gamse JT, Ess KC, Hardiman G, Lipschutz JH, Abumrad NN, Rockey DC. A post-developmental genetic screen for zebrafish models of inherited liver disease. PLoS One 2015; 10:e0125980. [PMID: 25950913 PMCID: PMC4423964 DOI: 10.1371/journal.pone.0125980] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 03/27/2015] [Indexed: 02/07/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease such as simple steatosis, nonalcoholic steatohepatitis (NASH), cirrhosis and fibrosis. However, the molecular pathogenesis and genetic variations causing NAFLD are poorly understood. The high prevalence and incidence of NAFLD suggests that genetic variations on a large number of genes might be involved in NAFLD. To identify genetic variants causing inherited liver disease, we used zebrafish as a model system for a large-scale mutant screen, and adopted a whole genome sequencing approach for rapid identification of mutated genes found in our screen. Here, we report on a forward genetic screen of ENU mutagenized zebrafish. From 250 F2 lines of ENU mutagenized zebrafish during post-developmental stages (5 to 8 days post fertilization), we identified 19 unique mutant zebrafish lines displaying visual evidence of hepatomegaly and/or steatosis with no developmental defects. Histological analysis of mutants revealed several specific phenotypes, including common steatosis, micro/macrovesicular steatosis, hepatomegaly, ballooning, and acute hepatocellular necrosis. This work has identified multiple post-developmental mutants and establishes zebrafish as a novel animal model for post-developmental inherited liver disease.
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Affiliation(s)
- Seok-Hyung Kim
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, the United States of America
- * E-mail:
| | - Shu-Yu Wu
- Department of Biology, Vanderbilt University, Nashville, TN, 37232, the United States of America
| | - Jeong-In Baek
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, the United States of America
| | - Soo Young Choi
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, the United States of America
| | - Yanhui Su
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, the United States of America
| | - Charles R. Flynn
- Department of Surgery, Vanderbilt University, Nashville, TN, 37232, the United States of America
| | - Joshua T. Gamse
- Department of Biology, Vanderbilt University, Nashville, TN, 37232, the United States of America
| | - Kevin C. Ess
- Department of Pediatrics, Vanderbilt University, Nashville, TN, 37232, the United States of America
| | - Gary Hardiman
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, the United States of America
| | - Joshua H. Lipschutz
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, the United States of America
- Department of Medicine, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC, 29401, the United States of America
| | - Naji N. Abumrad
- Department of Surgery, Vanderbilt University, Nashville, TN, 37232, the United States of America
| | - Don C. Rockey
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, the United States of America
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97
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Zhong R, Xu H, Chen G, Zhao G, Gao Y, Liu X, Ma S, Dong L. The role of hypoxia-inducible factor-1α in radiation-induced autophagic cell death in breast cancer cells. Tumour Biol 2015; 36:7077-83. [PMID: 25874499 DOI: 10.1007/s13277-015-3425-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Accepted: 04/06/2015] [Indexed: 12/21/2022] Open
Abstract
Hypoxia-inducible factor-1α (HIF-1α) is a major effector in cell survival response to hypoxia, while the roles of HIF-1α in radiation-induced autophagy are still unclear in breast cancer cells. Human breast cancer carcinoma MCF-7 cells were stably transfected with pSUPER-shRNA against human HIF-1α or a scrambled sequence with no homology to mammalian genes, named as pSUPER-HIF-1α and pSUPER-SC, respectively. Cell Counting Kit-8 (CCK-8) assay and colony formation assay were used to detect cell viability, Western blot was used to detect protein expression, monodansylcadaverine (MDC) staining was used to analyze autophagy, and Hoechts/PI staining was used to assess apoptosis. Ionizing radiation (IR) and cobalt chloride (CoCl2) could induce HIF-1α expression and increase the microtubule-associated protein 1 light chain 3 (MAPLC3)-II/MAPLC3-I ratio, especially in radiation + CoCl2 group. After the silencing of HIF-1α, the radiosensitivity of MCF-7 cells increased and the autophagy level decreased in response to DNA damage induced by ionizing radiation, but there was no influence on IR-induced apoptosis. HIF-1α silencing also increased the expression of phospho-Akt, mTOR, and P70S6K and activated the mTOR signals significantly. Hypoxia can induce autophagy and also improve the IR-induced autophagy via the suppression of Akt/mTOR/P70S6K pathway, which consequently lead to radioresistance.
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Affiliation(s)
- Rui Zhong
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, 130021, China
| | - Huiying Xu
- Department of Ultrasound, The 1st Hospitals Affiliated to Jilin University, Changchun, 130021, China
| | - Ge Chen
- Department of Stomatology, The 1st Hospitals Affiliated to Jilin University, Changchun, 130021, China
| | - Gang Zhao
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, 130021, China
| | - Yan Gao
- Department of Radiation Oncology, The 1st Hospitals Affiliated to Jilin University, Changchun, 130021, China
| | - Xiaodong Liu
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, 130021, China.,Department of Radiation Oncology, The 1st Hospitals Affiliated to Jilin University, Changchun, 130021, China
| | - Shumei Ma
- Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, 130021, China. .,Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, MB, R3T 3T2, Canada.
| | - Lihua Dong
- Department of Radiation Oncology, The 1st Hospitals Affiliated to Jilin University, Changchun, 130021, China.
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98
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Teaching the basics of autophagy and mitophagy to redox biologists--mechanisms and experimental approaches. Redox Biol 2015; 4:242-59. [PMID: 25618581 PMCID: PMC4803799 DOI: 10.1016/j.redox.2015.01.003] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 12/24/2014] [Accepted: 01/01/2015] [Indexed: 02/08/2023] Open
Abstract
Autophagy is a lysosomal mediated degradation activity providing an essential mechanism for recycling cellular constituents, and clearance of excess or damaged lipids, proteins and organelles. Autophagy involves more than 30 proteins and is regulated by nutrient availability, and various stress sensing signaling pathways. This article provides an overview of the mechanisms and regulation of autophagy, its role in health and diseases, and methods for its measurement. Hopefully this teaching review together with the graphic illustrations will be helpful for instructors teaching graduate students who are interested in grasping the concepts and major research areas and introducing recent developments in the field. mTOR, Beclin–VPS34, LC3 homologs, and adaptor proteins in autophagy. Autophagosomal membranes may derive from multiple sources. Autophagosomal–lysosomal fusion contributes to the control of autophagic flux. Assess autophagy by autophagosomal and protein turnover, and morphological alterations. Autophagy adysfunction in cancer, aging, neurodegeneration and infection.
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